1. Field of the Invention
This invention relates to measuring saddle pressures on a horse, and in particular, the distribution of pressure measured by a sensor array pad placed between a saddle and horse. The sensor array pad accommodates the compound curvature of the back of a horse by placing an array of sensors on a membrane support that is stretchable between sensors or sets of sensors on sections of the pad, or on a non-stretchable membrane support configured to conform to the compound curved surface.
2. Related Art
For centuries, people have ridden horses and fit a multitude of saddles on them with very little understanding of the effect of the saddle on the horse. Traditionally, saddle fit has been determined by riding the horse and then observing the sweat pattern on the horse's back.
It is expected that a majority of the over 10,000,000 horses in the United States and 3,500,000 in Europe may have sore backs from poorly fitting saddles. Since there is no recognized way to ask a horse how a saddle fits, there is a need for an apparatus that can be used to objectively measure the fit of a saddle on a horse.
Talley, Inc. of Romsey, England developed a pad formed of air cells that are connected to a controller unit via thin, flexible hard plastic tubes. Such a system is very cumbersome. Vistamed of Winnipeg, Canada developed an array using force-sensitive resistors,. A company known as Tekscan of Cambridge, Mass. developed an extensive and dense array using a force-sensitive ink printed on a polyester film.
A disadvantage of such pads, however, is that they are made for use in planar or simple curvature surfaces. When they are applied to a compound curvature surface, such as the back of a horse, they buckle and distort, preventing accurate and consistent determination of the pressures distributed across the surface of interest.
Sensor array pads are known to be used for mapping the pressure between a person and a wheel chair seat or bed surface. These systems include an array pad formed of pressure-responsive sensors distributed on a stretchable, flexible membrane. Signals from the sensors are converted to digital form and fed into a computer that then generates pressure distribution data that can be saved in memory, printed out, or displayed on a monitor.
It has been found that this system provides the necessary pressure mapping over a pad array area corresponding to the area of a wheel chair or bed. The stretchable, flexible membrane is found also to conform to the compound curvatures of a horses back. However, the sensor array size is inappropriate for use in measuring the distribution of pressures for an entire saddle. If it is set on one side of the saddle, it tends to migrate under the saddle. If it is placed over the spine of a horse, the sensors over the spine area are not used because the saddle does not rest on that area of a horse. Further, the membrane is manipulated and tends to become distorted over the spine, stressing the structural integrity of any sensors on the membrane. The sensors produce erroneous signals when not properly sandwiched between the horse and saddle.
Up to now, there has not been an apparatus or method of determining the amount and distribution of pressures between a saddle and a horse, particularly one that accommodates the shape of a horse's back and the structure of a saddle. Nor has there been a system that provides for improvement in the saddle/horse interface, such as by modifying the saddle structure or rider posture to alter the pressure distribution.